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Re: Muni fiber: L1 or L2?

From: Owen DeLong <owen () delong com>
Date: Thu, 31 Jan 2013 15:32:49 -0800
Scott,

Respectfully, you appear to be misinterpreting what I am saying.

I'm saying you put the splitter next to the OLT and then run multiple fibers from there to the subscribers IN THE MMR.
Each provider has their own splitters and OLTs, but all the splitters are in the MMR and the customers have home
run fiber to the MMR.

In other words:

OLT->SPLITTER->XC to customer port in MMR->Last mile infrastructure->ONT->Customer.
instead of the traditional
OLT->Last mile infrastructure->Splitter->ONT->Customer.

All I'm doing is moving the location of the split closer to the OLT and making the customer fiber run
longer.

I'm not proposing multiple providers sharing a splitter. I'm proposing longer customer runs to the
splitter and putting all of the splitters from all of the providers in the same room.

Owen

On Jan 31, 2013, at 14:04 , Scott Helms <khelms () zcorum com> wrote:


Owen,

Respectfully, it doesn't work that way.  You have to understand that the splitter is a specific part of the PON 
architecture and they don't have multiple outputs to connect to several OLTs like a patch panel or even a switch you 
can VLAN.  One fiber goes to the splitter on the provider side and then from there it splits into 8/16/32/64 
connections that go to customers.  You can't exchange one of the customer side ports to make another provider 
interface.  That's not to say you couldn't build a splitter to do just that, but to do that you have to get the 
vendors on board and currently they simply aren't nor are the people who build PON networks asking for that feature.  
You also have to deal with the mechanics of turning up the port, ie deciding which OLT to send that color to, which 
kind of kills the passive part of PON.


On Thu, Jan 31, 2013 at 4:36 PM, Owen DeLong <owen () delong com> wrote:

On Jan 31, 2013, at 13:27 , Scott Helms <khelms () zcorum com> wrote:


Owen,

You can't share access from one splitter to multiple OLTs so the location of the splitter isn't important.  AFAIK 
there is simply no concept for that idea in any of the PON specs and its certainly not something that 
Calix/Adtran/Zhone/Alcatel/$gear_maker are building right now.  For that matter I can't think of a single piece of 
gear beyond DWDM/CWDM that actually operates are layer 1 to allow that kind of split and then its very limited in 
terms of the channels available and not suitable for the kind of deployment I think you're describing.




Sure it is...

If you have an MMR where all of the customers come together, then you
can cross-connect all of $PROVIDER_1's customers to a splitter provided
by $PROVIDER_1 and cross connect all of $PROVIDER_2's customers to
a splitter provided by $PROVIDER_2, etc.

If the splitter is out in the neighborhood, then $PROVIDER_1 and $PROVIDER_2
and... all need to build out to every neighborhood.

If you have the splitter next to the PON gear instead of next to the subscribers,
then you remove the relevance of the inability to connect a splitter to multiple
OLTs. The splitter becomes the provider interface to the open fiber plant.

Owen



On Thu, Jan 31, 2013 at 4:15 PM, Owen DeLong <owen () delong com> wrote:
That's why I'm not advocating for open access, I'm advocating for L1/L2 provider
separation and a requirement that the L1 access itself be open.

I have yet to get a firm answer, but as I understand PON, it doesn't actually matter
so much whether you put the splitter/combiner in an MMR or near the CPE.
Obviously, most of the "economy" of PON comes from putting the splitter near
the subscriber, but so does the loss of open access at L1.

OTOH, if you build out fiber from a city or neighborhood or whatever to an
independent MMR, I don't believe there's any reason you couldn't cross-connect
various users home-run fibers to splitter/combiners inside the MMR and then
run that to a PON system (if you really wanted to for some reason).

Owen

On Jan 31, 2013, at 12:45 , Scott Helms <khelms () zcorum com> wrote:


Owen,

The short answer is that you don't today and it will be a long time (if ever) before its feasible.  Europe is 
commonly held up as an example of an area where open access works and if you stick to DSL networks that's true.  
The problem is that the DSL networks (by and large) in Europe aren't expanding and are being overtaken by FTTx and 
to a lesser extent DOCSIS.  The reasons why this is so can be debated, but it is definitely happening and given 
that trend there is very little incentive for the equipment manufacturers and protocol groups to build in open 
access as a core part of their design as it was in DSL, especially with PPPoX authentication.  

Now, once networks get to purely active Ethernet things get more simple technically, after all you easily do QinQ 
tagging, but there has been little movement even in regulation tolerant Europe to force operators to open up and 
its much less likely to happen here in the US.  Whats more many of the FTTx builds aren't Ethernet today and doing 
open access on any flavor of PON is so painful operationally that it simply won't happen.


On Thu, Jan 31, 2013 at 3:31 PM, Owen DeLong <owen () delong com> wrote:

On Jan 31, 2013, at 07:07 , Ray Soucy <rps () maine edu> wrote:


Late to the conversation, but I'll chime in that we established a
model in Maine that is working pretty well, at least for middle-mile
fiber.

When we started building out MaineREN (our RON) we decided that having
the University own the fiber would tie it up in political red tape.
So much so that it would ultimately not be made available to the
private sector (because incumbents would accuse us of competing with
them using public funds).  We knew this because we had already spent a
year in the legislature fighting off industry lobbyists.

Obviously there are considerable investments in such infrastructure
that many private companies are unwilling or unable to make in rural
areas (ROI takes too long), so we really wanted to make sure that
future facilities would be built out in a way that would allow service
providers to expand into the state cheaply, encourage competition, and
ultimately provide better services at lower costs.

The goal was to establish geographically diverse, high stand-count,
rings to reach the majority of the state, so we pitched it in a
public-private partnership to go after Recovery Act funding.



That's also a worthy goal, but it doesn't address the issues that
are the subject of this conversation. Middle-mile solutions
like this are not all that uncommon, even in such backwards
places (when it comes to networking infrastructure) as silicon
valley.

Where we still have a serious lack of deployment and virtually no
competition, even in most major metros, is the last mile.


As of a few months ago the build-out is complete, and the first
networks to make use of the fiber are starting to come online
(including MaineREN).

The way we did it was to have the state government create a new public
utility designation of "Dark Fiber Provider".  There are a few rules
in place to keep things fair: Mainly they're forbidden to provide lit
services and they're required to provide open access to anyone at
published rates.



This is definitely a good first step if you can get it through the legislative
process without having the $TELCOS and $CABLECOS lobby against
it to the point of death or dismemberment.


The result is "Maine Fiber Company":

http://www.mainefiberco.com/

It's still early on, but I'm anxious to see how things look in 10 years or so.



Sounds great... Now, the $50,000,000 question... How do we replicate
that model at the consumer level?


A lot of people who like the idea of what we've done aren't sure if
it's a good model to apply for last mile fiber.  Personally, I think
replicating this model to deliver dark fiber to the home (much like
electricity) is the only way we'll be able to shield providers from
having to make major investments to deliver the level of service we
really need.  By keeping it as a dark-fiber only service, you create
an environment where there is competition instead of one provider
keeping speeds low and prices high.


That's certainly the ideal, yes.


I initially thought having L2 separation would be good in that service
changes could be done remotely, etc.  But after giving it some
thought, I think it places way too much potential for L2 to be the
bottleneck or source of problematic service and if it's provided by a
public utility or municipality it could take very long to fix (if it
get's fixed at all) due to politics and budget hawks.  I really want
to have choice between providers even at the L2 level.


There are cases where the lack of L2 services could pose a barrier
to entry for competition. That's why I proposed the following requirements:

1.      Must sell dark fiber to any purchaser.
2.      Must sell dark fiber to all purchasers on equal terms.
        (There must be a published price list and there cannot be deviations
        from that price list. If the price list is modified, existing customers
        receive the new pricing at the beginning of their next billing cycle.)
3.      May provide value-added L2 services
4.      If L2 services are provided, they are also subject to rule 2.
5.      May not sell L3 or higher level services.
6.      May not hold ownership or build any form of alliance or affiliation with
        a provider of L3 or higher level services.

Owen






On Tue, Jan 29, 2013 at 12:54 PM, Jay Ashworth <jra () baylink com> wrote:

----- Original Message -----

From: "Leo Bicknell" <bicknell () ufp org>



I am a big proponent of muni-owned dark fiber networks. I want to
be 100% clear about what I advocate here:

- Muni-owned MMR space, fiber only, no active equipment allowed. A
big cross connect room, where the muni-fiber ends and providers are
all allowed to colocate their fiber term on non-discriminatory terms.



- 4-6 strands per home, home run back to the muni-owned MMR space.
No splitters, WDM, etc, home run glass. Terminating on an optical
handoff inside the home.


Hmmm.  I tend to be a Layer-2-available guy, cause I think it lets smaller
players play.  Does your position (likely more deeply thought out than
mine) permit Layer 2 with Muni ONT and Ethernet handoff, as long as clients
are *also* permitted to get a Layer 1 patch to a provider in the fashion you
suggest?

(I concur with your 3-pair delivery, which makes this more practical on an
M-A-C basis, even if it might require some users to have multiple ONTs...)

Cheers,
-- jra
--
Jay R. Ashworth                  Baylink                       jra () baylink com
Designer                     The Things I Think                       RFC 2100
Ashworth & Associates     http://baylink.pitas.com         2000 Land Rover DII
St Petersburg FL USA               #natog                      +1 727 647 1274





--
Ray Patrick Soucy
Network Engineer
University of Maine System

T: 207-561-3526
F: 207-561-3531

MaineREN, Maine's Research and Education Network
www.maineren.net






-- 
Scott Helms 
Vice President of Technology 
ZCorum 
(678) 507-5000 
-------------------------------- 
http://twitter.com/kscotthelms 
-------------------------------- 





-- 
Scott Helms 
Vice President of Technology 
ZCorum 
(678) 507-5000 
-------------------------------- 
http://twitter.com/kscotthelms 
-------------------------------- 





-- 
Scott Helms 
Vice President of Technology 
ZCorum 
(678) 507-5000 
-------------------------------- 
http://twitter.com/kscotthelms 
--------------------------------
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